Terminal apparatus and method

ABSTRACT

A terminal apparatus for communicating with a base station apparatus, the terminal apparatus including: a receiver configured to receive a radio resource control (RRC) reconfiguration message including data radio bearer (DRB) configuration from the base station apparatus; and a processing unit, wherein service data adaptation protocol (SDAP) configuration is included in the DRB configuration, and the processing unit determines whether to establish an SDAP entity, based on information for identifying a protocol data unit (PDU) session associated with the SDAP configuration.

TECHNICAL FIELD

The present invention relates to a terminal apparatus and a method.

This application claims priority based on JP 2017-219900 filed on Nov.15, 2017, the contents of which are incorporated herein by reference.

BACKGROUND ART

A radio access scheme and a radio network for cellular mobilecommunications (which will hereinafter be referred to as “Long TermEvolution (LTE; trade name)” or “Evolved Universal Terrestrial RadioAccess (EUTRA)”) and a core network (which will be referred to as“Evolved Packet Core or EPC”) have been studied by the 3rd GenerationPartnership Project (3GPP).

As a radio access scheme and a radio network technology for a5th-generation cellular system, technical studies and standardization ofLTE-Advanced Pro, which is an enhanced technology of LTE, and New Radiotechnology (NR), which is a new radio access technology, have beenconducted by the 3GPP (NPL 1). 5 Generation Core Network (5GC), which isa core network for a 5th generation cellular system, has also beenstudied (NPL 2).

CITATION LIST Non Patent Literature

NPL 1: 3GPP RP-170855, “Work Item on New Radio (NR) Access Technology”

NPL 2: 3GPP TS 23.501, “System Architecture for the 5G System; Stage 2”

NPL 3: 3GPP TS 36.300, “Evolved Universal Terrestrial Radio Access(E-UTRA) and Evolved Universal Terrestrial Radio Access Network(E-UTRAN); Overall description; Stage 2”

NPL 4: 3GPP TS 36.331, “Evolved Universal Terrestrial Radio Access(E-UTRA); Radio Resource Control (RRC); Protocol specifications”

NPL 5: 3GPP TS 36.323, “Evolved Universal Terrestrial Radio Access(E-UTRA); Packet Data Convergence Protocol (PDCP) specification”

NPL 6: 3GPP TS 36.322, “Evolved Universal Terrestrial Radio Access(E-UTRA); Radio Link Control (RLC) protocol specification”

NPL 7: 3GPP TS 36.321, “Evolved Universal Terrestrial Radio Access(E-UTRA); Medium Access Control (MAC) protocol specification”

NPL 8: 3GPP TS 37.340, “Evolved Universal Terrestrial Radio Access(E-UTRA) and NR; Multi-Connectivity; Stage 2”

NPL 9: 3GPP TS 38.300, “NR; NR and NG-RAN Overall description; Stage 2”

NPL 10: 3GPP TS 38.331, “NR; Radio Resource Control (RRC); Protocolspecifications”

NPL 11: 3GPP TS 38.323, “NR; Packet Data Convergence Protocol (PDCP)specification”

NPL 12: 3GPP TS 38.322, “NR; Radio Link Control (RLC) protocolspecification”

NPL 13: 3GPP TS 38.321, “NR; Medium Access Control (MAC) protocolspecification”

NPL 14: 3GPP TS 23.401 v14.3.0, “General Packet Radio Service (GPRS)enhancements for Evolved Universal Terrestrial Radio Access Network(E-UTRAN) access”

NPL 15: 3GPP TS 23.502, “Procedure for 5G System; Stage 2”

NPL 16: 3GPP TS 37.324, “NR; Service Data Adaptation Protocol (SDAP)specification”

SUMMARY OF INVENTION Technical Problem

As one of NR technical studies, protocols for a radio access layer arestudied which perform Quality of Service (QoS) management between higherlayers than the Internet Protocol (IP) layer and a radio access layer ofNR.

However, there is a problem in that the management of QoS cannot beperformed correctly, and communication between a base station apparatusand a terminal apparatus cannot be efficiently performed in a case thatnecessary information is not transmitted and/or received between thehigher layers and the radio access layer.

In view of the circumstances described above, an object of an aspect ofthe present invention is to provide a terminal apparatus capable ofefficiently communicating with base station apparatuses, a method usedfor the terminal apparatus, and an integrated circuit mounted on theterminal apparatus.

Solution to Problem

In order to accomplish the object described above, an aspect of thepresent invention is contrived to provide the following means.Specifically, an aspect of the present invention is a terminal apparatusfor communicating with one or more base station apparatuses, theterminal apparatus including: a receiver configured to receive an RRCreconfiguration message including information optionally indicating thatan SDAP header for uplink is present from a base station apparatus ofthe one or more base station apparatuses; a storage unit configured tostore mapping rules between QoS flows and DRBs; and a processing unitconfigured to receive an uplink SDAP SDU from a higher layer, and in acase that a DRB mapped to the uplink SDAP SDU is configured such that anSDAP header for uplink is present, create an SDAP header for uplink, andconfigure a value of a QoS flow identifier of a QoS flow correspondingto the uplink SDAP SDU to a QoS flow identifier field of the SDAP headerfor uplink.

An aspect of the present invention is a terminal apparatus forcommunicating with one or more base station apparatuses, the terminalapparatus including: a receiver configured to receive an RRCreconfiguration message including information optionally indicating thatan SDAP header for uplink is present from a base station apparatus ofthe one or more base station apparatuses; a storage unit configured tostore mapping rules between QoS flows and DRBs; and a processing unitconfigured to receive an uplink SDAP SDU from a higher layer, and in acase that a DRB mapped to the uplink SDAP SDU is configured such that anSDAP header for uplink is present, create an SDAP header for uplink, andconfigure a value of a QoS flow identifier of a QoS flow correspondingto the uplink SDAP SDU to a QoS flow identifier field of the SDAP headerfor uplink, wherein the SDAP header for uplink is configured to a DRBhaving a mapping rule with two or more QoS flows.

An aspect of the present invention is a method performed by a terminalapparatus for communicating with one or more base station apparatuses,the method including the steps of: receiving an RRC reconfigurationmessage including information optionally indicating that an SDAP headerfor uplink is present from a base station apparatus of the one or morebase station apparatuses; storing mapping rules between QoS flows andDRBs; receiving an uplink SDAP SDU from a higher layer; in a case that aDRB mapped to the uplink SDAP SDU is configured such that an SDAP headerfor uplink is present, creating an SDAP header for uplink; andconfiguring a value of a QoS flow identifier of a QoS flow correspondingto the uplink SDAP SDU to a QoS flow identifier field of the SDAP headerfor uplink.

An aspect of the present invention is a method performed by a terminalapparatus for communicating with one or more base station apparatuses,the method including the steps of: receiving an RRC reconfigurationmessage including information optionally indicating that an SDAP headerfor uplink is present from a base station apparatus of the base stationapparatuses; storing mapping rules between QoS flows and DRBs; receivingan uplink SDAP SDU from a higher layer; in a case that a DRB mapped tothe uplink SDAP SDU is configured such that an SDAP header for uplink ispresent; creating an SDAP header for uplink; and configuring a value ofa QoS flow identifier of a QoS flow corresponding to the uplink SDAP SDUto a QoS flow identifier field of the SDAP header for uplink, whereinthe SDAP header for uplink is configured to a DRB having a mapping rulewith two or more QoS flows.

These comprehensive or specific aspects may be implemented in a system,an apparatus, a method, an integrated circuit, a computer program, or arecording medium, or may be implemented in any combination of systems,apparatuses, methods, integrated circuits, computer programs, andrecording media.

Advantageous Effects of Invention

According to an aspect of the present invention, a terminal apparatuscan correctly perform QoS management and can communicate efficiently.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram of a communication system according toembodiments of the present invention.

FIG. 2 is a diagram of protocol stacks of the UP and the CP of aterminal apparatus and a base station apparatus in E-UTRA according toembodiments of the present invention.

FIG. 3 is a diagram of protocol stacks of the UP and the CP of aterminal apparatus and a base station apparatus in NR according toembodiments of the present invention.

FIG. 4 is a diagram illustrating an example of a flow of an RRCreconfiguration procedure according to each embodiment of the presentinvention.

FIG. 5 is a block diagram illustrating a configuration of a terminalapparatus according to embodiments of the present invention.

FIG. 6 is a diagram illustrating an example of information related toDRB configuration involved in SDAP configuration, and Abstract SyntaxNotation One (ASN.1) description of information, according to eachembodiment of the present invention.

FIG. 7 is an example of a processing method according to Embodiment 1 ofthe present invention.

FIG. 8 is an example of an SDAP header for uplink according toEmbodiment 1 of the present invention.

FIG. 9 is an example of a processing method according to Embodiment 2 ofthe present invention.

FIG. 10 is a first example of a processing method according toEmbodiment 3 of the present invention.

FIG. 11 is a second example of a processing method according toEmbodiment 3 of the present invention.

FIG. 12 is a third example of a processing method according toEmbodiment 3 of the present invention.

FIG. 13 is a block diagram illustrating a configuration of a terminalapparatus according to Embodiment 3 of the present invention.

DESCRIPTION OF EMBODIMENTS

Embodiments of the present invention will be described below in detailwith reference to the drawings.

LTE (and LTE-A Pro) and NR may be defined as different RATs. NR may bedefined as a technology included in LTE. LTE may be defined as atechnology included in NR. LTE capable of connecting with NR throughDual connectivity may be distinguished from conventional LTE. Thepresent embodiment may be applied to NR, LTE and other RATs. Termsassociated with LTE and NR are used in the following description.However, the present invention may be applied to other technologiesusing other terms.

FIG. 1 is a schematic diagram of a communication system according toembodiments of the present invention.

E-UTRA 100 is a radio access technology described in NPL 3 or the like,and is constituted by Cell Groups (CGs) configured in one or multiplefrequency bands. An E-UTRAN Node B (eNB) 102 is a base station apparatusof E-UTRA. An Evolved Packet Core (EPC) 104 is a core network describedin NPL 14 or the like and is designed as a core network for E-UTRA. Aninterface 112 is an interface between the eNB 102 and the EPC 104, wherethere is a Control Plane (CP) through which control signals transfer anda User Plane (UP) through which user data transfers.

NR 106 is a new radio access technology that is currently being studiedby the 3GPP and includes Cell Groups (CGs) that are configured in one ormultiple frequency bands. A gNode B (gNB) 108 is an NR base stationapparatus. A 5GC 110 is a new core network for NR which is currentlybeing studied by 3GPP, and is described in NPL 2 and the like.

An interface 114 is an interface between the eNB 102 and the 5GC 110, aninterface 116 is an interface between the gNB 108 and the 5GC 110, aninterface 118 is an interface between the gNB 108 and the EPC 104, aninterface 120 is an interface between the eNB 102 and the gNB 108, andan interface 124 is an interface between the EPC 104 and 5GC 110. Theinterface 114, the interface 116, the interface 118, the interface 120,and the interface 124 are interfaces that transfer the CP only, or theUP only, or both the CP and the UP, and details are being discussed by3GPP. The interface 114, the interface 116, the interface 118, theinterface 120, and the interface 124 may not exist depending oncommunication systems provided by network operators.

A UE 122 is a terminal apparatus supporting NR or supporting both E-UTRAand NR.

FIG. 2 is a diagram of Protocol Stacks of the UP and the CP of theterminal apparatus and the base station apparatus in the E-UTRA radioaccess layer according to embodiments of the present invention.

FIG. 2(A) is a diagram of a protocol stack of the UP used in a case thatthe UE 122 communicates with the eNB 102.

A Physical layer (PHY) 200 is a radio physical layer for providingtransmission services to higher layers by using Physical Channels. ThePHY 200 is connected with a Medium Access Control layer (MAC) 202, whichis a higher layer described below, via Transport Channels. Data isexchanged between the MAC 202 and the PHY 200 via the transportchannels. The data is transmitted and/or received via radio physicalchannels between the PHYs of the UE 122 and the eNB 102.

The MAC 202 maps various Logical Channels to various transport channels.The MAC 202 is connected with a Radio Link Control layer (RLC) 204,which is a higher layer described below, via logical channels. Thelogical channels are roughly classified depending on types ofinformation transmitted, specifically, classified into control channelstransmitting control information and traffic channels transmitting userinformation. The MAC 202 has a function of controlling the PHY 200 inorder to perform Discontinuous Reception and Transmission (DRX and DTX),a function of performing Random Access procedures, a function ofreporting transmit power information, a function of performing HARQcontrol, and the like (NPL 7).

An RLC 204 divides (Segmentation) data received from a Packet DataConvergence Protocol Layer (PDCP) 206, which is a higher layer describedbelow, and adjusts the data size such that lower layers can properlytransmit data. The RLC 200 also has a function of ensuring Quality ofService (QoS) required for each piece of data. In other words, the RLC204 has a function of data retransmission control or the like (NPL 6).

The PDCP 206 may have a header compression function for compressingunnecessary control information in order to efficiently transmit IPPackets, which are user data, in radio segments. The PDCP 206 may alsohave a data encryption function (NPL 5).

Note that data processed in the MAC 202, the RLC 204, and the PDCP 206is referred to as MAC Protocol Data Units (PDUs), RLC PDUs, and PDCPPDUs, respectively. Data transferred from a higher layer to the MAC 202,the RLC 204, and the PDCP 206, or data to be transferred to a higherlayer is referred to as MAC Service Data Units (SDUs), RLC SDUs, andPDCP SDUs, respectively.

FIG. 2(B) is a diagram of a protocol stack of the CP used in a case thatthe UE 122 communicates with the eNB 102.

In addition to the PHY 200, the MAC 202, the RLC 204, and the PDCP 206,there is a Radio Resource Control layer (RRC) 208 in the protocol stackof the CP. The RRC 208 performs configuration or reconfiguration ofRadio Bearers (RBs) to control logical channels, transport channels, andphysical channels. The RBs may be classified into Signaling RadioBearers (SRBs) and Data Radio Bearers (DRBs), and the SRBs may be usedas paths for transmitting RRC messages, which are control information.The DRBs may be used as paths for transmitting user data. Each RB may beconfigured in the RRCs 208 of the eNB 102 and the UE 122 (NPL 4).

The functional classification of the MAC 202, the RLC 204, the PDCP 206,and the RRC 208 described above is an example, and some or all of therespective functions may not be implemented. Some or all of thefunctions of each layer may be included in another layer.

FIG. 3 is a diagram of Protocol Stacks of the UP and CP of the terminalapparatus and the base station apparatus in the NR radio access layeraccording to embodiments of the present invention.

FIG. 3(A) is a diagram of a protocol stack of the UP used in a case thatthe UE 122 communicates with the gNB 108.

A Physical layer (PHY) 300 is a radio physical layer of NR and mayprovide transmission services to higher layers by using PhysicalChannels. The PHY 300 may be connected with a Medium Access Controllayer (MAC) 302, which is a higher layer described below, via TransportChannels. Data may be exchanged between the MAC 302 and the PHY 300 viathe transport channels. The data may be transmitted and/or receivedbetween the PHYs of the UE 122 and the gNB 108 via radio physicalchannels. Unlike the radio physical layer PHY 200 of E-UTRA, details ofthe PHY 200 are under discussion by 3GPP.

The MAC 302 may map various Logical Channels to various transportchannels. The MAC 302 may be connected with a Radio Link Control layer(RLC) 304, which is a higher layer described below, via logicalchannels. The logical channels are roughly classified depending on typesof information transmitted, and may be classified into control channelstransmitting control information and traffic channels transmitting userinformation. The MAC 302 may have a function of controlling the PHY 300in order to perform Discontinuous Reception and Transmission (DRX andDTX), a function of performing Random Access procedures, a function ofreporting transmit power information, a function of performing HARQcontrol, and the like (NPL 13). Unlike the MAC 202 of E-UTRA, details ofthe MAC 202 are under discussion by 3GPP.

The RLC 304 may divide (Segmentation) data received from a Packet DataConvergence Protocol Layer (PDCP) 206, which is a higher layer describedbelow, and adjust the data size such that lower layers can properlytransmit data. The RLC 304 may also have a function of ensuring Qualityof Service (QoS) required for each piece of data. In other words, theRLC 304 may have a function of data retransmission control or the like(NPL 12). Unlike the RLC 204 of E-UTRA, details of the RLC 204 are underdiscussion by 3GPP.

A PDCP 306 may have a header compression function for compressingunnecessary control information in order to efficiently transmit IPPackets, which are user data, in radio segments. The PDCP 306 may alsohave a data encryption function (NPL 11). Unlike the PDCP 206 of E-UTRA,details of the PDCP 306 are under discussion by 3GPP.

A Service Data Adaptation Protocol (SDAP) 310 performs mapping of QoSflows and DRBs of downlink transmitted from a core network to a terminalapparatus via a base station apparatus, and mapping of QoS informationflows and DRBs of uplink transmitted from a terminal apparatus to a corenetwork via a base station apparatus, and may have a function forstoring mapping rule information (NPL 16). QoS flows include one or moreService Data Flows (SDFs) that are processed by the same QoS policy (NPL2). The SDAP 310 may have a function of Reflective QoS for performingmapping of QoS flows and DRBs of uplink, based on information ofdownlink QoS flows (NPL 2 and NPL 16). Details are under discussion by3GPP.

Note that the IP layer, and the Transmission Control Protocol (TCP)layer, the User Datagram Protocol (UDP) layer, the application layer,and the like, which are higher than the IP layer, are higher layers ofthe SDAP (not illustrated). For the SDAP of a terminal apparatus, alayer for performing association between service data flows and QoSflows is also a higher layer of the SDAP.

Note that data processed in the MAC 302, the RLC 304, the PDCP 306, andthe SDAP 310 may be referred to as MAC Protocol Data Units (PDUs), RLCPDUs, PDCP PDUs, and SDAP PDUs, respectively. Data transferred from ahigher layer to the MAC 202, the RLC 204, and the PDCP 206, or data tobe transferred to a higher layer may be referred to as MAC Service DataUnits (SDUs), RLC SDUs, PDCP SDUs, and SDAP SDUs, respectively.

FIG. 3(B) is a diagram of a protocol stack of the CP used in a case thatthe UE 122 communicates with the gNB 108.

In addition to the PHY 300, the MAC 302, the RLC 304, and the PDCP 306,there is a Radio Resource Control layer (RRC) 308 in the protocol stackof the CP. The RRC 308 may perform configuration or reconfiguration ofRadio Bearers (RBs) to control logical channels, transport channels, andphysical channels. The RBs may be classified into Signaling RadioBearers (SRBs) and Data Radio Bearers (DRBs), and the SRBs may be usedas paths for transmitting RRC messages, which are control information.The DRBs may be used as paths for transmitting user data. Each RB may beconfigured in the RRCs 308 of the gNB 108 and the UE 122 (NPL 10).

The functional classification of the MAC 302, the RLC 304, the PDCP 306,the SDAP 310, and the RRC 308 described above is an example, and some orall of the respective functions may not be implemented. Some or all ofthe functions of each layer may be included in another layer.

Note that, in embodiments of the present invention, the MAC 202, the RLC204, the PDCP 206, and the RRC 208 may be referred to as the MAC forE-UTRA or the MAC for LTE, the RLC for E-UTRA or the RLC for LTE, thePDCP for E-UTRA or the PDCP for LTE, and the RRC for E-UTRA or the RRCfor LTE, respectively, to distinguish protocols of E-UTRA and NRhereinbelow. The MAC 302, the RLC 304, the PDCP 306, and the RRC 308 mayalso be referred to as the MAC for NR, the RLC for NR, the RLC for NR,and the RRC for NR, respectively.

As also illustrated in FIG. 1, the eNB 102, the gNB 108, the EPC 104,and the 5GC 110 may be connected to one another via the interface 112,the interface 116, the interface 118, the interface 120, and theinterface 114. Thus, the RRC 208 in FIG. 2 may be replaced with the RRC308 in FIG. 3 to support various communication systems. The PDCP 206 inFIG. 2 may also be replaced with the PDCP 306 in FIG. 3. The RRC 308 inFIG. 3 may include functions of the RRC 208 in FIG. 2. The PDCP 306 inFIG. 3 may be the PDCP 206 in FIG. 2.

Embodiment 1

Embodiment 1 of the present invention will be described with referenceto FIG. 1 and FIG. 4 to FIG. 8.

FIG. 4 is a diagram illustrating an example of a flow of an RRCreconfiguration procedure according to each embodiment of the presentinvention.

The RRC Reconfiguration procedure includes procedures used for handoverand Measurement and the like, in addition to establishment, change, andrelease of RBs, and change, release, and the like of secondary cells inNR as disclosed in NPL 10. According to each embodiment of the presentinvention, procedures used for establishment, change, and release ofRBs, addition, change, and release of cell groups, handover andMeasurement, and the like in NR may be referred to as RRCreconfiguration procedures, or may have another designation. Theprocedures used for establishment, change, and release of RBs, addition,change, and release of cell groups, handover and Measurement, and thelike according to each embodiment of the present invention may beprocedures in E-UTRA according to NPL 4, or may be referred to as RRCconnection reconfiguration procedures.

In an RRC reconfiguration procedure, the UE 122 receives an RRCreconfiguration message (RRCReconfigration) from the gNB 108 (stepS400), and performs various configurations according to informationincluded in the RRC reconfiguration message, such as configuration ofDRBs (step S402). After step S402, the UE 122 may transmit an RRCreconfiguration complete message (RRCReconfigrationComplete) and thelike to the gNB 108 (not illustrated).

FIG. 5 is a block diagram illustrating a configuration of a terminalapparatus (UE 122) according to embodiments of the present invention.Note that FIG. 5 illustrates only main components closely related to anaspect of the present invention in order to avoid complicatedexplanation.

The UE 122 illustrated in FIG. 5 includes a receiver 500 configured toreceive RRC reconfiguration messages from the gNB 108, a storage unit502 configured to store mapping rules between QoS flows and DRBs, and aprocessing unit 504 configured to process messages and data.

FIG. 6 is an example of information related to DRB configurationinvolved in SDAP configuration, and Abstract Syntax Notation One(ASN. 1) description of information, among the information included inthe RRC reconfiguration message in FIG. 4. The specifications related toRRC (NPL 4 and NPL 10) in the 3GPP describe messages, information(Information Element or IE), and the like related to RRC by using ASN.1.In the example of ASN.1 of FIG. 6, <omitted> or <partly omitted>indicates that not part of the description of ASN.1, but other pieces ofinformation are omitted. Note that there may also be omitted informationin parts where neither <omitted> nor <partly omitted> is indicated. Notethat the example of ASN.1 in FIG. 6 does not exactly follow thedescription method of ASN.1, but is a description of an example ofparameters of SDAP configuration according to an aspect of the presentinvention, and other names or other descriptions may be used. Theexample of ASN.1 in FIG. 6 only illustrates examples about maininformation closely related to an aspect of the present invention inorder to avoid complicated explanation.

The information represented by DRB-ToAddModList in FIG. 6 may be a listof information indicating configuration of DRBs to be added or modified,represented by DRBToAddMod. The information represented bypduSession-Identity in DRB-ToAddMod (information indicatingconfiguration of DRBs to be added or modified) may be informationidentifying a PDU session described in NPL 2. The informationidentifying a PDU session may be a PDU session identifier described inNPL 2 or may be other information. In the example of FIG. 6, theinformation identifying a PDU session is an integer value from 1 to 16,but may take another value. The information identifying a PDU sessionmay be used to identify a PDU session associated with a DRB to beconfigured. In FIG. 6, the information identifying a PDU session isincluded in information indicating configuration of DRBs to be added ormodified, but may be described elsewhere. The information represented byDRB-Identity in the information indicating configuration of DRBs to beadded or modified is a DRB identity of a DRB to be added or modified. Inthe example of FIG. 6, the information represented by DRB-Identity is aninteger value from 1 to 32, but may take another value. The DRB identitymay be used to uniquely identify a DRB in a PDU session.

In FIG. 6, the information represented by sdap-Config in the informationindicating configuration of DRBs to be added or modified may beinformation related to SDAP entity configuration. The informationrepresented by qosFlowIdAddList in the information related to SDAPentity configuration may be list information of QoS flow identifiers(QoSFlow-Identity) corresponding (mapping) to DRB identities. The QoSflow identifiers corresponding (mapping) to DRBs may be correspondence(mapping) in the uplink direction. A QoS flow identifier may be aninteger value. The information represented by qosFlowIdReleaseList inthe information related to SDAP entity configuration may be listinformation of QoS flow identifiers (QoSFlow-Identity) to be releasedfrom among QoS flow identifiers corresponding (mapping) to DRBidentities.

The information represented by sdapHeader-UL may be informationindicating that an SDAP header for uplink is present in SDAP PDUs in theuplink direction corresponding (mapping) to DRBs to be configured. Theinformation indicating that an SDAP header for uplink is present may betranslated in that an SDAP header for uplink is necessary in SDAP PDUsor SDAP SDUs in the uplink direction corresponding (mapping) to DRBs tobe configured. The information represented by sdapHeader-DL may beinformation indicating that an SDAP header for downlink is present inSDAP PDUs in the downlink direction corresponding (mapping) to DRBs tobe configured. The information indicating that an SDAP header for uplinkis present, and the information indicating that an SDAP header foruplink is present may indicate that it is present by using true, enable,or the like, or may indicate that it is present with a numerical valuerepresenting a header length.

The information represented by reflective may be information indicatingthat DRBs to be configured correspond (mapping) to reflective QoS flowsdescribed in NPL 2 and NPL 16. The information indicating that DRBs tobe configured correspond (mapping) to reflective QoS flows may indicatethat DRBs to be configured correspond (mapping) to reflective QoS flowsby using true, enable, or the like. Note that in each embodiment of thepresent invention, a QoS flow may include one or more Service Data Flows(SDFs) that are processed by the same QoS policy (NPL 2). Note that areflective QoS flow may indicate a QoS flow in which a Reflective QoSIndicator (RQI) for being handled as a reflective QoS is included in anencapsulated header (N3 header) of user data of a core network of eachpacket of one or more SDFs among SDFs assigned to QoS flows.

The information indicated by default may be information indicating thatDRBs to be added or modified are default DRBs. The default DRBs may beDRBs corresponding to QoS flows with a default QoS policy, or may beDRBs mapped in a case that mapping rules between QoS flows and DRBscorresponding to uplink SDAP SDUs are not stored. The informationindicating that DRBs to be added or modified are default DRBs mayindicate that DRBs to be added or modified are default DRBs by usingtrue, enable, and the like.

The information indicated by DRB-ToReleaseList may be informationindicating a list of DRB identities of DRBs to be released.

Some or all of the information illustrated in FIG. 6 may be optional. Inother words, the information illustrated in FIG. 6 may be included in anRRC reconfiguration message as necessary. Different processing may bedefined as processing of the UE 122 in cases that the information isincluded or not included in an RRC reconfiguration message. For example,the information indicating that an SDAP header for uplink is present,the information indicating that an SDAP header for downlink is present,the information indicating that DRBs to be configured correspond(mapping) to reflective QoS flows, the information indicating that DRBsto be added or modified are default DRBs, and the like may be optional.

The information illustrated in FIG. 6 may include information havingdependencies. For example, in a case that the number of QoS flowidentifiers included in list information of QoS flow identifiers(QoSFlow-Identity) corresponding (mapping) to DRB identities is two ormore, or the number of QoS flows corresponding (mapping) to one DRB istwo or more, it may mean that information is present which indicatesthat an SDAP header for uplink is present. Even in a case that thenumber of QoS flows corresponding (or mapping) to one DRB is two ormore, it may mean that a case of default DRBs is excluded, that is,information is not present which indicates that an SDAP header foruplink is present. Conversely, it may mean that, in a case of defaultDRBs, information is present which indicates that an SDAP header foruplink is present.

For example, in a case that information indicating that DRBs to beconfigured correspond (mapping) to reflective QoS flows is included inan RRC reconfiguration message, it may mean that information is presentwhich indicates that an SDAP header for downlink is present.

Note that the information indicating that an SDAP header for downlink ispresent may be information indicating that DRBs to be configuredcorrespond (mapping) to reflective QoS flows. In other words, in a casethat the information indicating that an SDAP header for downlink ispresent in an RRC reconfiguration message, it may indicate that an SDAPheader for downlink is present, and DRBs to be configured correspond(mapping) to reflective QoS flows.

FIG. 7 illustrates an example of a processing method of the processingunit 504 of the UE 122 in FIG. 5, according to Embodiment 1 of thepresent invention.

FIG. 8 illustrates an example of an SDAP header for uplink according toEmbodiment 1 of the present invention.

Next, an example of a DRB configuration procedure including SDAPconfiguration in an RRC reconfiguration procedure will be described withreference to FIG. 4 to FIG. 8.

The receiver 500 of the UE 122 receives an RRC reconfiguration messagefrom the gNB 108 (step S400). The processing unit 504 of the UE 122performs configuration in accordance with information included in theRRC reconfiguration message (step S402). The RRC reconfiguration messagein Embodiment 1 of the present invention includes information indicatingthat an SDAP header for uplink is present in information related to SDAPentity configuration. In a case that DRB identities and list informationof QoS flow identifiers corresponding (mapping) to DRB identities areincluded in the RRC reconfiguration message, the processing unit 504 ofthe UE 122 creates mapping rules between QoS flows corresponding to theQoS flow identifiers for uplink and DRBs having the DRB identities tostore in the storage unit 502. At this time, the processing unit 504 ofthe UE 122 may notify higher layers of information of storing, togetherwith the QoS flow identifiers. In a case that the RRC reconfigurationmessage includes list information of QoS flow identifiers to bereleased, the processing unit 504 of the UE 122 releases mapping rulesbetween QoS flows for uplink and DRBs stored in the storage unit 502,corresponding (mapping) to QoS flow identifiers included in the listinformation of the QoS flow identifiers to be released. At this time,the processing unit 504 of the UE 122 may notify higher layers ofinformation of releasing, together with the QoS flow identifiers. In acase that the RRC reconfiguration message includes list information ofDRB identities to be released, the processing unit 504 of the UE 122releases mapping rules between QoS flows for uplink and DRBs stored inthe storage unit 502, corresponding (mapping) to DRB identities includedin the list information of the DRB identities to be released. At thistime, the processing unit 504 of the UE 122 may notify higher layers ofinformation of releasing, together with the QoS flow identifiers.

Next, the processing unit 504 of the UE 122 receives an SDAP SDU and aQoS Flow Identifier (QFI) of a QoS flow corresponding (mapping) to theSDAP SDU from a higher layer (step S700).

Next, the processing unit 504 of the UE 122 checks whether or not theDRB mapped to the SDAP SDU received from the higher layer is a DRBconfigured such that an SDAP header for uplink is present, and in a casethat the DRB is configured such that an SDAP header for uplink ispresent, creates an SDAP header for uplink (step S702).

FIGS. 8(A) and 8(B) are examples of formats of an SDAP header for uplinkaccording to Embodiment 1 of the present invention. FIGS. 8(A) and 8(B)both include a QFI field and R fields (R bits). The R field (R bits) isa reserved field (reserved bits). In FIG. 8(A), there is one 1-bitlength R field, whereas there is one 7-bit length QFI field. In FIG.8(B), there are two 1-bit length R fields (or one 2-bit length R field),while there is one 6-bit length QFI field. Note that the format of anSDAP header for uplink is not always as this format, but, for example,instead of the R field, there may be a reflective indicator field (RQIfield). There may also be other fields or bits, for example, fields orbits indicating that there are no mapping rules between QoS flows andDRBs corresponding to SDAP PDUs received from a higher layer.

Next, the processing unit 504 of the UE 122 configures the QFI of theQoS flow corresponding to the SDAP PDU received from the higher layer instep S700, to the QFI field of the SDAP header for uplink. Theprocessing unit 504 of the UE 122 may set zero (‘0’) to the reservedfield of the SDAP header for uplink (step S704). Note that in a casethat an RQI field is present in the SDAP header for uplink, theprocessing unit 504 of the UE 122 may set zero (‘0’) to the RQI field.

Next, the processing unit 504 of the UE 122 adds the SDAP header foruplink generated in step S702 and step S704 to the SDAP SDU receivedfrom the higher layer in step S700 to create an SDAP PDU, and submitsthe SDAP PDU to a lower layer according to mapping rules between QoSflows and DRBs stored in the storage unit 502. Note that the order ofstoring values to each field of an SDAP header for uplink from step S700to step S706 and adding an SDAP header for uplink to an SDAP SDU may notbe this order. Note that in a case that the SDAP header for uplink isnot configured to be present in step S702, an SDAP header for uplink maynot be created, and the SDAP SDU received from the higher layer may besubmitted as is, as an SDAP PDU to a lower layer.

As described above, in Embodiment 1 of the present invention, theterminal apparatus can perform efficient communication by transmittingand/or receiving necessary information such as QoS flow identifierinformation between higher layers and radio access layer to correctlymanaging QoS.

Embodiment 2

Embodiment 2 of the present invention will be described with referenceto FIG. 1, and FIG. 4 to FIG. 6, and FIG. 9. FIG. 4 to FIG. 6 are thesame as in Embodiment 1 of the present invention.

In other words, FIG. 4 is a diagram illustrating an example of a flow ofan RRC reconfiguration procedure according to each embodiment of thepresent invention.

The RRC Reconfiguration procedure includes procedures used for handoverand Measurement and the like, in addition to establishment, change, andrelease of RBs, and change, release, and the like of secondary cells inNR as disclosed in NPL 10. According to each embodiment of the presentinvention, procedures used for establishment, change, and release ofRBs, addition, change, and release of cell groups, handover andMeasurement, and the like in NR may be referred to as RRCreconfiguration procedures, or may have another designation. Theprocedures used for establishment, change, and release of RBs, addition,change, and release of cell groups, handover and Measurement, and thelike according to each embodiment of the present invention may beprocedures in E-UTRA according to NPL 4, or may be referred to as RRCconnection reconfiguration procedures.

In an RRC reconfiguration procedure, the UE 122 receives an RRCreconfiguration message (RRCReconfigration) from the gNB 108 (stepS400), and performs various configurations according to informationincluded in the RRC reconfiguration message, such as configuration ofDRBs (step S402). After step S402, the UE 122 may transmit an RRCreconfiguration complete message (RRCReconfigrationComplete) and thelike to the gNB 108 (not illustrated).

FIG. 5 is a block diagram illustrating a configuration of a terminalapparatus (UE 122) according to each embodiment of the presentinvention. Note that FIG. 5 illustrates only main components closelyrelated to an aspect of the present invention in order to avoidcomplicated explanation.

The UE 122 illustrated in FIG. 5 includes a receiver 500 configured toreceive RRC reconfiguration messages from the gNB 108, a storage unit502 configured to store mapping rules between QoS flows and DRBs, and aprocessing unit 504 configured to process messages and data.

FIG. 6 is an example of information related to DRB configurationinvolved in SDAP configuration, and Abstract Syntax Notation One (ASN.1)description of information, among the information included in the RRCreconfiguration message in FIG. 4. The specifications related to RRC(NPL 4 and NPL 10) in the 3GPP describe messages, information(Information Element or IE), and the like related to RRC by using ASN.1.In the example of ASN.1 of FIG. 6, <omitted> or <partly omitted>indicates that not part of the description of ASN.1, but other pieces ofinformation are omitted. Note that there may also be omitted informationin parts where neither <omitted> nor <partly omitted> is indicated. Notethat the example of ASN.1 in FIG. 6 does not exactly follow thedescription method of ASN.1, but is a description of an example ofparameters of SDAP configuration according to an aspect of the presentinvention, and other names or other descriptions may be used. Theexample of ASN.1 in FIG. 6 only illustrates examples about maininformation closely related to an aspect of the present invention inorder to avoid complicated explanation.

The information represented by DRB-ToAddModList in FIG. 6 may be a listof information indicating configuration of DRBs to be added or modified,represented by DRBToAddMod. The information represented bypduSession-Identity in DRB-ToAddMod (information indicatingconfiguration of DRBs to be added or modified) may be informationidentifying a PDU session described in NPL 2. The informationidentifying a PDU session may be a PDU session identifier described inNPL 2 or may be other information. In the example of FIG. 6, theinformation identifying a PDU session is an integer value from 1 to 16,but may take another value. The information identifying a PDU sessionmay be used to identify a PDU session associated with a DRB to beconfigured. In FIG. 6, the information identifying a PDU session isincluded in information indicating configuration of DRBs to be added ormodified, but may be described elsewhere. The information represented byDRB-Identity in the information indicating configuration of DRBs to beadded or modified is a DRB identity of a DRB to be added or modified. Inthe example of FIG. 6, the information represented by DRB-Identity is aninteger value from 1 to 32, but may take another value. The DRB identitymay be used to uniquely identify a DRB in a PDU session.

In FIG. 6, the information represented by sdap-Config in the informationindicating configuration of DRBs to be added or modified may beinformation related to SDAP entity configuration. The informationrepresented by qosFlowIdAddList in the information related to SDAPentity configuration may be list information of QoS flow identifiers(QoSFlow-Identity) corresponding (mapping) to DRB identities. The QoSflow identifiers corresponding (mapping) to DRBs may be correspondence(mapping) in the uplink direction. A QoS flow identifier may be aninteger value. The information represented by qosFlowIdReleaseList inthe information related to SDAP entity configuration may be listinformation of QoS flow identifiers (QoSFlow-Identity) to be releasedfrom among QoS flow identifiers corresponding (mapping) to DRBidentities.

The information represented by sdapHeader-UL may be informationindicating that an SDAP header for uplink is present in SDAP PDUs in theuplink direction corresponding (mapping) to DRBs to be configured. Theinformation indicating that an SDAP header for uplink is present may betranslated in that an SDAP header for uplink is necessary in SDAP PDUsor SDAP SDUs in the uplink direction corresponding (mapping) to DRBs tobe configured. The information represented by sdapHeader-DL may beinformation indicating that an SDAP header for downlink is present inSDAP PDUs in the downlink direction corresponding (mapping) to DRBs tobe configured. The information indicating that an SDAP header for uplinkis present, and the information indicating that an SDAP header foruplink is present may indicate that it is present by using true, enable,or the like, or may indicate that it is present with a numerical valuerepresenting a header length.

The information represented by reflective may be information indicatingthat DRBs to be configured correspond (mapping) to reflective QoS flowsdescribed in NPL 2 and NPL 16. The information indicating that DRBs tobe configured correspond (mapping) to reflective QoS flows may indicatethat DRBs to be configured correspond (mapping) to reflective QoS flowsby using true, enable, or the like. Note that in each embodiment of thepresent invention, a QoS flow may include one or more Service Data Flows(SDFs) that are processed by the same QoS policy (NPL 2). Note that areflective QoS flow may indicate a QoS flow in which a Reflective QoSIndicator (RQI) for being handled as a reflective QoS is included in anencapsulated header (N3 header) of user data of a core network of eachpacket of one or more SDFs among SDFs assigned to QoS flows.

The information indicated by default may be information indicating thatDRBs to be added or modified are default DRBs. The default DRBs may beDRBs corresponding (mapping) to QoS flows with a default QoS policy, ormay be DRBs mapped in a case that mapping rules between QoS flows andDRBs corresponding to uplink SDAP SDUs are not stored. The informationindicating that DRBs to be added or modified are default DRBs mayindicate that DRBs to be added or modified are default DRBs by usingtrue, enable, and the like.

The information indicated by DRB-ToReleaseList may be informationindicating a list of DRB identities of DRBs to be released.

Some or all of the information illustrated in FIG. 6 may be optional. Inother words, the information illustrated in FIG. 6 may be included in anRRC reconfiguration message as necessary. Different processing may bedefined as processing of the UE 122 in cases that the information isincluded or not included in an RRC reconfiguration message. For example,the information indicating that an SDAP header for uplink is present,the information indicating that an SDAP header for downlink is present,the information indicating that DRBs to be configured correspond(mapping) to reflective QoS flows, the information indicating that DRBsto be added or modified are default DRBs, and the like may be optional.

The information illustrated in FIG. 6 may include information havingdependencies. For example, in a case that the number of QoS flowidentifiers included in list information of QoS flow identifiers(QoSFlow-Identity) corresponding (mapping) to DRB identities is two ormore, or the number of QoS flows corresponding (mapping) to one DRB istwo or more, it may mean that information is present which indicatesthat an SDAP header for uplink is present. Even in a case that thenumber of QoS flows corresponding (or mapping) to one DRB is two ormore, it may mean that a case of default DRBs is excluded, that is,information is not present which indicates that an SDAP header foruplink is present. Conversely, it may mean that, in a case of defaultDRBs, information is present which indicates that an SDAP header foruplink is present.

For example, in a case that information indicating that DRBs to beconfigured correspond (mapping) to reflective QoS flows is included inan RRC reconfiguration message, it may mean that information is presentwhich indicates that an SDAP header for downlink is present.

Note that the information indicating that an SDAP header for downlink ispresent may be information indicating that DRBs to be configuredcorrespond (mapping) to reflective QoS flows. In other words, in a casethat the information indicating that an SDAP header for downlink ispresent in an RRC reconfiguration message, it may indicate that an SDAPheader for downlink is present, and DRBs to be configured correspond(mapping) to reflective QoS flows.

FIG. 9 illustrates an example of a processing method of the processingunit 504 of the UE 122 in FIG. 5, according to Embodiment 2 of thepresent invention.

Next, an example of a DRB configuration procedure including SDAPconfiguration in an RRC reconfiguration procedure according toEmbodiment 2 of the present invention will be described with referenceto FIG. 4 to FIG. 6 and FIG. 9.

The receiver 500 of the UE 122 receives an RRC reconfiguration messagefrom the gNB 108 (step S400). The processing unit 504 of the UE 122performs configuration in accordance with information included in theRRC reconfiguration message (step S402). The RRC reconfiguration messagein Embodiment 2 of the present invention includes information indicatingcorresponding (mapping) to reflective QoS flows, information indicatingthat an SDAP header for downlink is present, or information indicatingcorresponding (mapping) to reflective QoS flows and informationindicating that an SDAP header for downlink is present, in theinformation related to SDAP entity configuration. In a case that DRBidentities and list information of QoS flow identifiers corresponding(mapping) to DRB identities are included in the RRC reconfigurationmessage, the processing unit 504 of the UE 122 creates mapping rulesbetween QoS flows corresponding to the QoS flow identifiers for uplinkand DRBs having the DRB identities to store in the storage unit 502. Atthis time, the processing unit 504 of the UE 122 may notify higherlayers of information of storing, together with the QoS flowidentifiers. In a case that the RRC reconfiguration message includeslist information of QoS flow identifiers to be released, the processingunit 504 of the UE 122 releases mapping rules between QoS flows foruplink and DRBs stored in the storage unit 502, corresponding (mapping)to QoS flow identifiers included in the list information of the QoS flowidentifiers to be released. At this time, the processing unit 504 of theUE 122 may notify higher layers of information of releasing, togetherwith the QoS flow identifiers. In a case that the RRC reconfigurationmessage includes list information of DRB identities to be released, theprocessing unit 504 of the UE 122 releases mapping rules between QoSflows for uplink and DRBs stored in the storage unit 502, corresponding(mapping) to DRB identities included in the list information of the DRBidentities to be released. At this time, the processing unit 504 of theUE 122 may notify higher layers of information of releasing, togetherwith the QoS flow identifiers.

Next, the processing unit 504 of the UE 122 receives a downlink SDAP PDUfrom a lower layer (step S900).

Next, the processing unit 504 of the UE 122 checks whether or not theDRB that receives the downlink SDAP PDU is configured such that an SDAPheader for downlink is present, and in a case that the DRB is configuredsuch that an SDAP header for downlink is present, processes the SDAPheader for downlink of the received downlink SDAP PDU (step S902).

Next, the processing unit 504 of the UE 122 checks whether the field ofthe RQI of the SDAP header for downlink is a value (‘0’) indicating thatthe reflective QoS indication is action (step S904). In a case that theRQI field is a value (‘0’) indicating reflective QoS indicationnon-action, the processing unit 504 of the UE 122 removes the SDAPheader for downlink from the downlink SDAP PDU received from the lowerlayer in step S900 to create an SDAP SDU and transfer the SDAP SDU to ahigher layer (step S906).

In a case that the field of the RQI of the SDAP header for downlink is 1in step S902, the processing unit 504 of the UE 122 further checkswhether or not a mapping rule between a QoS flow for uplink and a DRBcorresponding to a value of a QFI included in an SDAP header fordownlink is stored in the storage unit 502 (step S908). In a case thatthe mapping rule is stored in the storage unit 502, the processing unit504 of the UE 122 removes the header for downlink from the SDAP PDUreceived from the lower layer in step S900 to create an SDAP SDU, andtransfers the value of the QFI included in the SDAP header for downlinkand information indicating reflective indication action (RQI=1) to ahigher layer along with the SDAP SDU (step S912). Here, by transferringthe value of the QFI included in the SDAP header for downlink to thehigher layer along with the SDAP SDU, it may also serve to transferinformation of a reflective indication.

In a case that a mapping rule between a QoS flow for uplink and a DRBcorresponding to a value of a QFI included in an SDAP header fordownlink are not stored in the storage unit 502 in step S908, theprocessing unit 504 of the UE 122 stores a mapping rule between a QoSflow for uplink and a DRB corresponding to the value of the QFI includedin the SDAP header for downlink in the storage unit 502 (step S910), andremoves the header for downlink from the SDAP PDU for downlink receivedfrom the lower layer in step S900 to create an SDAP SDU, and transfersthe value of the QFI included in the SDAP header for downlink and theinformation of reflective indication to a higher layer along with theSDAP SDU (step S912). Here, by transferring the value of the QFIincluded in the SDAP header for downlink to the higher layer along withthe SDAP SDU, it may also serve to transfer information of a reflectiveindication.

Note that, from step S900 to step S912, the order of removing an SDAPheader for downlink from an SDAP PDU to generate an SDAP SDU, the orderfor analyzing a field of a downlink SDAP header, and the order ofstoring a mapping rule between a QoS flow for uplink and a DRBcorresponding to a value of a QFI included in an SDAP header fordownlink in the storage unit 502 may not as those illustrated. Note thatin a case that an SDAP header for downlink is not configured to bepresent in step S902, the processing unit 504 of the UE 122 may pass theSDAP PDU for downlink received from the lower layer as is, as an SDAPSDU to a higher layer.

Note that, instead of checking whether or not a mapping rule between aQoS flow for uplink and a DRB corresponding to a value of a QFI includedin the SDAP header for downlink is stored in the storage unit 502 instep S908, the processing unit 504 of the UE 122 may check whether ornot a mapping rule between a QoS flow for uplink and a DRB correspondingto a value of a QFI included in the SDAP header stored in the storageunit 502 is active. At this time, in a case that a mapping rule betweena QoS flow for uplink and a DRB corresponding to a value of a QFIincluded in the SDAP header for downlink stored in the storage unit 502is not active, then, instead of storing a mapping rule for a QoS flowfor uplink and a DRB corresponding to a value of a QFI included in theSDAP header for downlink in the storage unit 502, the processing unit504 of the UE 122 may activate a mapping rule between a QoS flow foruplink and a DRB corresponding to a value of a QFI included in the SDAPheader for downlink stored in the storage unit 502 in step S910.

As described above, in Embodiment 2 of the present invention, theterminal apparatus can perform efficient communication by transmittingand/or receiving necessary information such as QoS flow identifierinformation and reflective QoS indication information between higherlayers and radio access layer to correctly managing QoS.

Embodiment 3

Embodiment 3 of the present invention will be described with referenceto FIG. 1, FIG. 4, FIG. 6, and FIG. 10 to FIG. 13. FIG. 4 and FIG. 6 arethe same as in Embodiment 1 of the present invention and Embodiment 2 ofthe present invention.

In other words, FIG. 4 is a diagram illustrating an example of a flow ofan RRC reconfiguration procedure according to each embodiment of thepresent invention.

The RRC Reconfiguration procedure includes procedures used for handoverand Measurement and the like, in addition to establishment, change, andrelease of RBs, and change, release, and the like of secondary cells inNR as disclosed in NPL 10. According to each embodiment of the presentinvention, procedures used for establishment, change, and release ofRBs, addition, change, and release of cell groups, handover andMeasurement, and the like in NR may be referred to as RRCreconfiguration procedures, or may have another designation. Theprocedures used for establishment, change, and release of RBs, addition,change, and release of cell groups, handover and Measurement, and thelike according to each embodiment of the present invention may beprocedures in E-UTRA according to NPL 4, or may be referred to as RRCconnection reconfiguration procedures.

In an RRC reconfiguration procedure, the UE 122 receives an RRCreconfiguration message (RRCReconfigration) from the gNB 108 (stepS400), and performs various configurations according to informationincluded in the RRC reconfiguration message, such as configuration ofDRBs (step S402). After step S402, the UE 122 may transmit an RRCreconfiguration complete message (RRCReconfigrationComplete) and thelike to the gNB 108 (not illustrated).

FIG. 6 is an example of information related to DRB configurationinvolved in SDAP configuration, and Abstract Syntax Notation One (ASN.1)description of information, among the information included in the RRCreconfiguration message in FIG. 4. The specifications related to RRC(NPL 4 and NPL 10) in the 3GPP describe messages, information(Information Element or IE), and the like related to RRC by using ASN.1.In the example of ASN.1 of FIG. 6, <omitted> or <partly omitted>indicates that not part of the description of ASN.1, but other pieces ofinformation are omitted. Note that there may also be omitted informationin parts where neither <omitted> nor <partly omitted> is indicated. Notethat the example of ASN.1 in FIG. 6 does not exactly follow thedescription method of ASN.1, but is a description of an example ofparameters of SDAP configuration according to an aspect of the presentinvention, and other names or other descriptions may be used. Theexample of ASN.1 in FIG. 6 only illustrates examples about maininformation closely related to an aspect of the present invention inorder to avoid complicated explanation.

The information represented by DRB-ToAddModList in FIG. 6 may be a listof information indicating configuration of DRBs to be added or modified,represented by DRBToAddMod. The information represented bypduSession-Identity in DRB-ToAddMod (information indicatingconfiguration of DRBs to be added or modified) may be informationidentifying a PDU session described in NPL 2. The informationidentifying a PDU session may be a PDU session identifier described inNPL 2 or may be other information. In the example of FIG. 6, theinformation identifying a PDU session is an integer value from 1 to 16,but may take another value. The information identifying a PDU sessionmay be used to identify a PDU session associated with a DRB to beconfigured. In FIG. 6, the information identifying a PDU session isincluded in information indicating configuration of DRBs to be added ormodified, but may be described elsewhere. The information represented byDRB-Identity in the information indicating configuration of DRBs to beadded or modified is a DRB identity of a DRB to be added or modified. Inthe example of FIG. 6, the information represented by DRB-Identity is aninteger value from 1 to 32, but may take another value. The DRB identitymay be used to uniquely identify a DRB in a PDU session.

In FIG. 6, the information represented by sdap-Config in the informationindicating configuration of DRBs to be added or modified may beinformation related to SDAP entity configuration. The informationrepresented by qosFlowIdAddList in the information related to SDAPentity configuration may be list information of QoS flow identifiers(QoSFlow-Identity) corresponding (mapping) to DRB identities. The QoSflow identifiers corresponding (mapping) to DRBs may be correspondence(mapping) in the uplink direction. A QoS flow identifier may be aninteger value. The information represented by qosFlowIdReleaseList inthe information related to SDAP entity configuration may be listinformation of QoS flow identifiers (QoSFlow-Identity) to be releasedfrom among QoS flow identifiers corresponding (mapping) to DRBidentities.

The information represented by sdapHeader-UL may be informationindicating that an SDAP header for uplink is present in SDAP PDUs in theuplink direction corresponding (mapping) to DRBs to be configured. Theinformation indicating that an SDAP header for uplink is present may betranslated in that an SDAP header for uplink is necessary in SDAP PDUsor SDAP SDUs in the uplink direction corresponding (mapping) to DRBs tobe configured. The information represented by sdapHeader-DL may beinformation indicating that an SDAP header for downlink is present inSDAP PDUs in the downlink direction corresponding (mapping) to DRBs tobe configured. The information indicating that an SDAP header for uplinkis present, and the information indicating that an SDAP header foruplink is present may indicate that it is present by using true, enable,or the like, or may indicate that it is present with a numerical valuerepresenting a header length.

The information represented by reflective may be information indicatingthat DRBs to be configured correspond (mapping) to reflective QoS flowsdescribed in NPL 2 and NPL 16. The information indicating that DRBs tobe configured correspond (mapping) to reflective QoS flows may indicatethat DRBs to be configured correspond (mapping) to reflective QoS flowsby using true, enable, or the like. Note that in each embodiment of thepresent invention, a QoS flow may include one or more Service Data Flows(SDFs) that are processed by the same QoS policy (NPL 2). Note that areflective QoS flow may indicate a QoS flow in which a Reflective QoSIndicator (RQI) for being handled as a reflective QoS is included in anencapsulated header (N3 header) of user data of a core network of eachpacket of one or more SDFs among SDFs assigned to QoS flows.

The information indicated by default may be information indicating thatDRBs to be added or modified are default DRBs. The default DRBs may beDRBs corresponding (mapping) to QoS flows with a default QoS policy, ormay be DRBs mapped in a case that mapping rules between QoS flows andDRBs corresponding (mapping) to uplink SDAP SDUs are not stored. Theinformation indicating that DRBs to be added or modified are defaultDRBs may indicate that DRBs to be added or modified are default DRBs byusing true, enable, and the like.

The information indicated by DRB-ToReleaseList may be informationindicating a list of DRB identities of DRBs to be released.

Some or all of the information illustrated in FIG. 6 may be optional. Inother words, the information illustrated in FIG. 6 may be included in anRRC reconfiguration message as necessary. Different processing may bedefined as processing of the UE 122 in cases that the information isincluded or not included in an RRC reconfiguration message. For example,the information indicating that an SDAP header for uplink is present,the information indicating that an SDAP header for downlink is present,the information indicating that DRBs to be configured correspond(mapping) to reflective QoS flows, the information indicating that DRBsto be added or modified are default DRBs, and the like may be optional.

The information illustrated in FIG. 6 may include information havingdependencies. For example, in a case that the number of QoS flowidentifiers included in list information of QoS flow identifiers(QoSFlow-Identity) corresponding (mapping) to DRB identities is two ormore, or the number of QoS flows corresponding (mapping) to one DRB istwo or more, it may mean that information is present which indicatesthat an SDAP header for uplink is present. Even in a case that thenumber of QoS flows corresponding (or mapping) to one DRB is two ormore, it may mean that a case of default DRBs is excluded, that is,information is not present which indicates that an SDAP header foruplink is present. Conversely, it may mean that, in a case of defaultDRBs, information is present which indicates that an SDAP header foruplink is present.

For example, in a case that information indicating that DRBs to beconfigured correspond (mapping) to reflective QoS flows is included inan RRC reconfiguration message, it may mean that information is presentwhich indicates that an SDAP header for downlink is present.

Note that the information indicating that an SDAP header for downlink ispresent may be information indicating that DRBs to be configuredcorrespond (mapping) to reflective QoS flows. In other words, in a casethat the information indicating that an SDAP header for downlink ispresent in an RRC reconfiguration message, it may indicate that an SDAPheader for downlink is present, and DRBs to be configured correspond(mapping) to reflective QoS flows.

FIG. 13 is a block diagram illustrating a configuration of a terminalapparatus (UE 122) according to Embodiment 3 of the present invention.Note that FIG. 5 illustrates only main components closely related to anaspect of the present invention in order to avoid complicatedexplanation.

The UE 122 illustrated in FIG. 13 includes a receiver 1300 configured toreceive an RRC reconfiguration message from the gNB 108, and aprocessing unit 1302 configured to perform processing in accordance withthe RRC reconfiguration request.

Next, a first example of a DRB configuration procedure in an RRCreconfiguration procedure according to Embodiment 3 of the presentinvention will described with reference to FIG. 4, FIG. 6, FIG. 10, andFIG. 13.

The receiver 1300 of the UE 122 receives an RRC reconfiguration messagefrom the gNB 108 (step S400). The processing unit 1302 of the UE 122performs configuration in accordance with information included in theRRC reconfiguration request (step S402).

FIG. 10 illustrates a first example of a processing method of theprocessing unit 1302 of the UE 122, according to Embodiment 3 of thepresent invention. The processing unit 1302 of the UE 122 checks a casethat information related to SDAP entity configuration is included ininformation indicating configuration of a DRB including a DRB identitythat is not in part of the current configuration of the UE 122, in alist of information indicating configuration of a DRB to be added ormodified, included in the RRC reconfiguration message received from thereceiver 1300, and whether or not information identifying a PDU sessionsuch as a PDU session identifier associated with the SDAP entityconfiguration is present in part of the current configuration of the UE122 configuration (step S1000). In a case that the informationidentifying the PDU session is not in part of the current configurationof the UE 122 configuration, after establishing an SDAP entity andperforming DRB configuration according to the information indicating theconfiguration of the DRB to be added or modified, the processing unit1302 of the UE 122 notifies a higher layer of QoS flow identifiers or alist of QoS flow identifiers corresponding (mapping) to the establishedDRB, and DRB establishment information (step S1002). At this time, theprocessing unit 1302 of the UE 122 may notify the informationidentifying the PDU session together. In a case that the informationidentifying the PDU session is in part of the current configuration ofthe UE 122 configuration, after reconfiguring the SDAP entity andperforming DRB configuration according to the information indicating theconfiguration of the DRB to be added or modified, the processing unit1302 of the UE 122 notifies a higher layer of QoS flow identifiers or alist of QoS flow identifiers corresponding (mapping) to established DRB,and DRB establishment information (step S1004). At this time, theprocessing unit 1302 of the UE 122 may notify the informationidentifying the PDU session together.

Next, a second example of a DRB configuration procedure in an RRCreconfiguration procedure according to Embodiment 3 of the presentinvention will be described with reference to FIG. 4 to FIG. 6 and FIG.11.

The receiver 1300 of the UE 122 receives an RRC reconfiguration messagefrom the gNB 108 (step S400). The processing unit 1302 of the UE 122performs configuration in accordance with information included in theRRC reconfiguration request (step S402).

FIG. 11 illustrates a second example of a processing method of theprocessing unit 1302 of the UE 122, according to Embodiment 3 of thepresent invention. The processing unit 1302 of the UE 122 checks thatthe RRC reconfiguration message received from the receiver 1300 includesinformation related to a list of QoS flow identifiers to be released(step S1100). At this time, the RRC reconfiguration message may includeDRB identities corresponding (mapping) to the QoS flow identifiers to bereleased. Next, the processing unit 1302 of the UE 122 notifies a higherlayer of the released QoS flow identifiers included in the list of theQoS flow identifiers released and information of releasing (step S1104).At this time, the processing unit 1302 of the UE 122 may notifyinformation identifying PDU sessions corresponding each of the releasedQoS flow identifiers together.

Next, a third example of a DRB configuration procedure in an RRCreconfiguration procedure according to Embodiment 3 of the presentinvention will be described with reference to FIG. 4 to FIG. 6 and FIG.12.

The receiver 1300 of the UE 122 receives an RRC reconfiguration messagefrom the gNB 108 (step S400). The processing unit 1302 of the UE 122performs configuration in accordance with information included in theRRC reconfiguration request (step S402).

FIG. 12 illustrates a third example of a processing method of theprocessing unit 1302 of the UE 122, according to Embodiment 3 of thepresent invention. The processing unit 1302 of the UE 122 checks thatthe RRC reconfiguration message includes a list of DRB identities to bereleased (step S1200). Next, the processing unit 1302 of the UE 122reconfigures the SDAP entity in a case that the DRB identities to bereleased are DRB identities associated with the SDAP entity, andnotifies a higher layer of the QoS flow identifiers corresponding(mapping) to DRBs having the DRB identities to be released, or the listof the QoS identifiers, and the information of releasing (step S1202).At this time, the processing unit 1302 of the UE 122 may notifyinformation identifying PDU sessions corresponding each of the releasedQoS flow identifiers together. Note that in a case that the DRBidentities to be released are not associated with the SDAP entity andare DRB identities associated with EPS bearer identifiers, the EPSbearer identifiers may be notified to a higher layer.

As described above, in Embodiment 3 of the present invention, theterminal apparatus can perform efficient communication by transmittingand/or receiving information of QoS flow identifiers corresponding(mapping) to DRBs between higher layers and the radio access layer tocorrectly managing QoS.

Note that the DRB configuration according to each embodiment of thepresent invention may be included in an RRC Establishment procedure oran RRC Re-Establishment procedure, in addition to an RRC reconfigurationprocedure.

A program running on an apparatus according to an aspect of the presentinvention may serve as a program that controls a Central Processing Unit(CPU) and the like to cause a computer to operate in such a manner as torealize the functions of the above-described embodiments according to anaspect of the present invention. Programs or the information handled bythe programs are temporarily read into a volatile memory, such as aRandom Access Memory (RAM) while being processed, or stored in anon-volatile memory, such as a flash memory, or a Hard Disk Drive (HDD),and then read by the CPU to be modified or rewritten, as necessary.

Note that the apparatuses in the above-described embodiments may bepartially enabled by a computer. In such a case, a program for realizingsuch control functions may be recorded on a computer-readable recordingmedium to cause a computer system to read the program recorded on therecording medium to perform the program. It is assumed that the“computer system” mentioned here refers to a computer system built intothe apparatuses, and the computer system includes an operating systemand hardware components such as a peripheral device. The“computer-readable recording medium” may be any of a semiconductorrecording medium, an optical recording medium, a magnetic recordingmedium, and the like.

Moreover, the “computer-readable recording medium” may include a mediumthat dynamically retains a program for a short period of time, such as acommunication line that is used to transmit the program over a networksuch as the Internet or over a communication line such as a telephoneline, and may also include a medium that retains a program for a fixedperiod of time, such as a volatile memory within the computer system forfunctioning as a server or a client in such a case. The above-describedprogram may be configured to realize some of the functions describedabove, and additionally may be configured to realize the functionsdescribed above, in combination with a program already recorded in thecomputer system.

Each functional block or various characteristics of the apparatuses usedin the above-described embodiments may be implemented or performed on anelectric circuit, that is, typically an integrated circuit or multipleintegrated circuits. An electric circuit designed to perform thefunctions described in the present specification may include ageneral-purpose processor, a Digital Signal Processor (DSP), anApplication Specific Integrated Circuit (ASIC), a Field ProgrammableGate Array (FPGA), or other programmable logic devices, discrete gatesor transistor logic, discrete hardware components, or a combinationthereof. The general-purpose processor may be a microprocessor, or theprocessor may be a processor of known type, a controller, amicro-controller, or a state machine instead. The general-purposeprocessor or the above-mentioned circuits may include a digital circuit,or may include an analog circuit. In a case that with advances insemiconductor technology, a circuit integration technology appears thatreplaces the present integrated circuits, it is also possible to use anintegrated circuit based on the technology.

Note that the invention of the present patent application is not limitedto the above-described embodiments. In the embodiment, apparatuses havebeen described as an example, but the invention of the presentapplication is not limited to these apparatuses, and is applicable to aterminal apparatus or a communication apparatus of a fixed-type or astationary-type electronic apparatus installed indoors or outdoors, forexample, an AV apparatus, a kitchen apparatus, a cleaning or washingmachine, an air-conditioning apparatus, office equipment, a vendingmachine, and other household apparatuses.

The embodiments of the present invention have been described in detailabove referring to the drawings, but the specific configuration is notlimited to the embodiments and includes, for example, an amendment to adesign that falls within the scope that does not depart from the gist ofthe present invention. Various modifications are possible within thescope of one aspect of the present invention defined by claims, andembodiments that are made by suitably combining technical meansdisclosed according to the different embodiments are also included inthe technical scope of the present invention. A configuration in whichconstituent elements, described in the embodiments and having mutuallythe same effects, are substituted for one another is also included inthe technical scope of the present invention.

INDUSTRIAL APPLICABILITY

An aspect of the present invention can be utilized, for example, in acommunication system, communication equipment (for example, a cellularphone apparatus, a base station apparatus, a wireless LAN apparatus, ora sensor device), an integrated circuit (for example, a communicationchip), or a program.

REFERENCE SIGNS LIST

-   100 E-UTRA-   102 eNB-   104 EPC-   106 NR-   108 gNB-   110 5GC-   112, 114, 116, 118, 120, 124 Interface-   122 UE-   200, 300 PHY-   202, 302 MAC-   204, 304 RLC-   206, 306 PDCP-   208, 308 RRC-   310 SDAP-   500, 1300 Receiver-   502 Storage unit-   504, 1302 Processing unit

The invention claimed is:
 1. A terminal apparatus for communicating with a base station apparatus, the terminal apparatus comprising: a receiver configured to receive a radio resource control (RRC) reconfiguration message including data radio bearer (DRB) configuration from the base station apparatus; and a processing unit, wherein a service data adaptation protocol (SDAP) configuration is included in the DRB configuration, and the processing unit is configured to: determine whether information for identifying a protocol data unit (PDU) session associated with the SDAP configuration is not part of a current terminal apparatus configuration, and establish an SDAP entity, in a case that the information is not part of the current terminal apparatus configuration.
 2. A base station apparatus for communicating with a terminal apparatus, the base station apparatus comprising: a transmitter configured to transmit a radio resource control (RRC) reconfiguration message including data radio bearer (DRB) configuration to the terminal apparatus, wherein a service data adaptation protocol (SDAP) configuration is included in the DRB configuration, and the base station apparatus is configured to cause the terminal apparatus to: determine whether information for identifying a protocol data unit (PDU) session associated with the SDAP configuration is not part of a current terminal apparatus configuration, and establish an SDAP entity, in a case that the information is not part of the current terminal apparatus configuration.
 3. A communication method used by a terminal apparatus for communicating with a base station apparatus, the communication method comprising: receiving a radio resource control (RRC) reconfiguration message including data radio bearer (DRB) configuration from the base station apparatus, wherein a service data adaptation protocol (SDAP) configuration is included in the DRB configuration; determining whether information for identifying a protocol data unit (PDU) session associated with the SDAP configuration is not part of a current terminal apparatus configuration; and establishing an SDAP entity, in a case that the information is not part of the current terminal apparatus configuration.
 4. A communication method used by a base station apparatus for communicating with a terminal apparatus, the communication method comprising: transmitting a radio resource control (RRC) reconfiguration message including data radio bearer (DRB) configuration to the terminal apparatus, wherein a service data adaptation protocol (SDAP) configuration is included in the DRB configuration; and causing the terminal apparatus is caused to: determine whether information for identifying a protocol data unit (PDU) session associated with the SDAP configuration is not part of a current terminal apparatus configuration, and establish an SDAP entity, in a case that the information is not part of the current terminal apparatus configuration. 